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    Thread: Front end rubbing noise when accelerating forward hard

    1. Junior Member Farzad's Avatar
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      Feb 18th, 2015
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      Los Angeles
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      1983 Rabbit GTI
      09-15-2020 02:13 AM #1
      This is the noise I hear in my 1983 rabbit gti when accelerating hard forward, either from a standstill or while rolling. Taking off hard in reverse produces no noise. Also, the noise is more difficult to reproduce when the engine is cold.

      I just replaced all four engine /gearbox mounts but the noise is still there. I have to say that i also have chatter when engaging the clutch quickly, not sure if they could be related.

      It sounds like something rubbing against a rotating member - something touching the drive shaft under load maybe? I guess I could check the clearance between the drive shafts and anything near by. I do have the gokraut underbody x/k brace installed, and a tech tonics exhaust. Any ideas on how I can diagnose this?
      '83 Rabbit GTI
      '06 Lotus Elise
      '19 Subaru Outback 3.6

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    3. Junior Member Farzad's Avatar
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      Feb 18th, 2015
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      Los Angeles
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      1983 Rabbit GTI
      09-15-2020 02:23 AM #2
      '83 Rabbit GTI
      '06 Lotus Elise
      '19 Subaru Outback 3.6

    4. Member BMAN's Avatar
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      Jun 9th, 1999
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      84 Rabbit GTI 95 Cabrio 1.8T 12 Golf TDI
      09-15-2020 08:11 AM #3
      Have you checked all your exhaust hangers? It sounds like your exhaust is rubbing against the body or suspension.

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    6. Senior Member briano1234's Avatar
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      Feb 20th, 2004
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      Atlanta Ga
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      90, 92, 93 Cabriolet They own you.
      09-15-2020 11:03 AM #4
      Quote Originally Posted by BMAN View Post
      Have you checked all your exhaust hangers? It sounds like your exhaust is rubbing against the body or suspension.
      If your exhaust which you didn't mention if it was upgraded to a different manifold/downpipe where the piece comes out of the down and over to the Cat or cat delete.
      When you jam it, the engine torques to the front of the grill Valance, this torque can cause the tail piece to contact the steering rack and or the cat cover plate and vibrate similar to what I am hearing, if it is hitting the rack you may feel a slight vibration in the steering wheel as well.

      If your tail pipe out of the down to the rear of your car isn't centered the it can rattle on the heat shielding that may be close to the resonator or cat.

      Last thing I had was that a front sway bar strap broke free and allowed the sway bar to run against the cv occasionally.

      In reverse you get the same torgue to the front but because you are in reverse the engine torques to the rear and down unlike forward motion where it torques to the front and up. This difference is that the muffler piping is forced to the front of the car where clearances when stationary are close, and when reving they meet...

      You didn't mention if you replaced the mounts with poly bushings or mounts, which in itself have been known to rattle the fillings in your teeth, or if you used the hard mount from valance for sprinters. I have found that when I replaced my front valance mount, that if I used 2 large fender washers on each side of the mount that it fit tighter and limited the Torque of the engine to the front drastically.

      If you have the heat shield over the CAT then check the clearances of it as the bolts that hold it in place can loosen and cause a rattle at torque that you hear.


      You may want to Jack the Car and place on jack stands then start the engine and rev it while watching it, to see if you can see where the noise is coming from.

      Cold versus hot, tends to make me think of connections in the Muffler that when cold are tight but when warmed they loosen up a wee bit because of one pipe expanding more than the other.

    7. Member
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      Dec 27th, 2005
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      81 S, 84 GTI, 86 16V, 92 Cabby
      09-15-2020 11:12 AM #5
      If all of the above check out, consider "Self-Machining-Syndrome": the final drive ring gear is riveted onto the differential housing and the rivets are known to loosen/fail. In the final run to catastrophic blowout of the transmission case, you get funny grinding noise like you're hearing.

      If that's what you're experiencing, it might be difficult to confirm without disassembly, so the best option might be to keep a good used gearbox on hand for the day you need it. If the clutch ends up being the problem or if you're due for clutch replacement soon anyways, you can replace the gearbox then as a precaution or open your gearbox to examine the rivets and/or upgrade them to the available bolt kit.
      It's hard for me to know exactly what these things cost me. I'm guessing a LOT, but I like them, so that's that.

    8. Member vwpieces's Avatar
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      83 TD Jetta, 68 Bus, 83 2dr Jetta 16V, 1971 Kawasaki H1 500
      09-15-2020 11:53 AM #6
      TT exhaust like to rub at the back on the fuel tank strap.
      Try a rubber pad between that pipe and strap go for ride again...

      Also down pipes tend to rub on the sway bar. Never ran the kraut front sub but possible issue there?

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